2 * Copyright (c) 2004-2005 Silicon Graphics, Inc.
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 #include "xfs_types.h"
22 #include "xfs_trans.h"
26 #include "xfs_dmapi.h"
27 #include "xfs_mount.h"
28 #include "xfs_export.h"
29 #include "xfs_vnodeops.h"
30 #include "xfs_bmap_btree.h"
31 #include "xfs_inode.h"
34 * Note that we only accept fileids which are long enough rather than allow
35 * the parent generation number to default to zero. XFS considers zero a
36 * valid generation number not an invalid/wildcard value.
38 static int xfs_fileid_length(int fileid_type)
40 switch (fileid_type) {
41 case FILEID_INO32_GEN:
43 case FILEID_INO32_GEN_PARENT:
45 case FILEID_INO32_GEN | XFS_FILEID_TYPE_64FLAG:
47 case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG:
50 return 255; /* invalid */
55 struct dentry *dentry,
60 struct fid *fid = (struct fid *)fh;
61 struct xfs_fid64 *fid64 = (struct xfs_fid64 *)fh;
62 struct inode *inode = dentry->d_inode;
66 /* Directories don't need their parent encoded, they have ".." */
67 if (S_ISDIR(inode->i_mode) || !connectable)
68 fileid_type = FILEID_INO32_GEN;
70 fileid_type = FILEID_INO32_GEN_PARENT;
72 /* filesystem may contain 64bit inode numbers */
73 if (!(XFS_M(inode->i_sb)->m_flags & XFS_MOUNT_SMALL_INUMS))
74 fileid_type |= XFS_FILEID_TYPE_64FLAG;
77 * Only encode if there is enough space given. In practice
78 * this means we can't export a filesystem with 64bit inodes
79 * over NFSv2 with the subtree_check export option; the other
80 * seven combinations work. The real answer is "don't use v2".
82 len = xfs_fileid_length(fileid_type);
87 switch (fileid_type) {
88 case FILEID_INO32_GEN_PARENT:
89 spin_lock(&dentry->d_lock);
90 fid->i32.parent_ino = dentry->d_parent->d_inode->i_ino;
91 fid->i32.parent_gen = dentry->d_parent->d_inode->i_generation;
92 spin_unlock(&dentry->d_lock);
94 case FILEID_INO32_GEN:
95 fid->i32.ino = inode->i_ino;
96 fid->i32.gen = inode->i_generation;
98 case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG:
99 spin_lock(&dentry->d_lock);
100 fid64->parent_ino = dentry->d_parent->d_inode->i_ino;
101 fid64->parent_gen = dentry->d_parent->d_inode->i_generation;
102 spin_unlock(&dentry->d_lock);
104 case FILEID_INO32_GEN | XFS_FILEID_TYPE_64FLAG:
105 fid64->ino = inode->i_ino;
106 fid64->gen = inode->i_generation;
113 STATIC struct inode *
115 struct super_block *sb,
119 xfs_mount_t *mp = XFS_M(sb);
124 * NFS can sometimes send requests for ino 0. Fail them gracefully.
127 return ERR_PTR(-ESTALE);
129 error = xfs_iget(mp, NULL, ino, 0, XFS_ILOCK_SHARED, &ip, 0);
131 return ERR_PTR(-error);
133 return ERR_PTR(-EIO);
135 if (ip->i_d.di_gen != generation) {
136 xfs_iput_new(ip, XFS_ILOCK_SHARED);
137 return ERR_PTR(-ENOENT);
140 xfs_iunlock(ip, XFS_ILOCK_SHARED);
144 STATIC struct dentry *
145 xfs_fs_fh_to_dentry(struct super_block *sb, struct fid *fid,
146 int fh_len, int fileid_type)
148 struct xfs_fid64 *fid64 = (struct xfs_fid64 *)fid;
149 struct inode *inode = NULL;
151 if (fh_len < xfs_fileid_length(fileid_type))
154 switch (fileid_type) {
155 case FILEID_INO32_GEN_PARENT:
156 case FILEID_INO32_GEN:
157 inode = xfs_nfs_get_inode(sb, fid->i32.ino, fid->i32.gen);
159 case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG:
160 case FILEID_INO32_GEN | XFS_FILEID_TYPE_64FLAG:
161 inode = xfs_nfs_get_inode(sb, fid64->ino, fid64->gen);
165 return d_obtain_alias(inode);
168 STATIC struct dentry *
169 xfs_fs_fh_to_parent(struct super_block *sb, struct fid *fid,
170 int fh_len, int fileid_type)
172 struct xfs_fid64 *fid64 = (struct xfs_fid64 *)fid;
173 struct inode *inode = NULL;
175 switch (fileid_type) {
176 case FILEID_INO32_GEN_PARENT:
177 inode = xfs_nfs_get_inode(sb, fid->i32.parent_ino,
178 fid->i32.parent_gen);
180 case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG:
181 inode = xfs_nfs_get_inode(sb, fid64->parent_ino,
186 return d_obtain_alias(inode);
189 STATIC struct dentry *
191 struct dentry *child)
194 struct xfs_inode *cip;
196 error = xfs_lookup(XFS_I(child->d_inode), &xfs_name_dotdot, &cip, NULL);
198 return ERR_PTR(-error);
200 return d_obtain_alias(VFS_I(cip));
203 const struct export_operations xfs_export_operations = {
204 .encode_fh = xfs_fs_encode_fh,
205 .fh_to_dentry = xfs_fs_fh_to_dentry,
206 .fh_to_parent = xfs_fs_fh_to_parent,
207 .get_parent = xfs_fs_get_parent,